Funding for this research was provided by:
National 13th Five-Year Grand Program on Key Infectious Disease Control (2018ZX10721102-003-003, 2018ZX10302-102, 2017ZX10202102-005–003, 2017ZX10202101-004–001)
National Natural Science Foundation of China (81601795)
the National Natural Science Foundation of China (81772165)
Received: 11 March 2020
Accepted: 2 July 2020
First Online: 9 July 2020
Ethics approval and consent to participate
: This study was approved by the Beijing Youan Hospital Research Ethics Committee (No. 2019–057). The participants received both written and oral information about the study before they gave their written informed consent. The participants were also assured of confidentiality.
: Not applicable.
: The authors declare that they have no competing interests.